A deviated nasal septum may increase the risk of sleep apnea syndrome, but there is no direct cause-and-effect relationship. A deviated nasal septum can cause nasal stenosis and poor ventilation, which may increase respiratory resistance during sleep and indirectly contribute to or exacerbate obstructive sleep apnea hypopnea syndrome (OSAHS).
The Relationship Between Nasal Septum Deviation And Sleep Apnea
Because the patient opens their mouth during sleep, this reflex narrows the pharyngeal cavity (the space in the center of the pharynx that allows food to pass through) in two ways, leading to sleep apnea and snoring.
When the mouth is opened during sleep, the jaw and the rest of the mandible move backward and downward, causing the tongue to move in that direction. This directly narrows the pharyngeal airway. Secondly, opening the mouth reduces the length and tone of the muscles surrounding the airway, thereby increasing airway resistance.
Attempting to breathe through the nose despite an obstruction increases negative pressure in the chest cavity. If the upper airway is narrowed at any point, according to Bernoulli’s principle, the pressure will cause the narrowed area to collapse, leading to apnea during sleep.
This hypothesis was further supported when nasal septal deformity, a common cause of nasal airway narrowing, was found to be highly prevalent in patients with sleep apnea syndrome.
Nasal obstruction does not directly cause sleep apnea because the airway does not collapse through the nose. However, there is an indirect link between a deviated septum and sleep apnea.
Therefore, clearing obstructions from your nasal passages will help you breathe better during sleep and even prevent airway collapse and sleep apnea.
The relationship between nasal septum deviation and sleep apnea syndrome is as follows:
1. Indirect association
A deviated nasal septum alone rarely causes apnea directly. Still, it may work in conjunction with other factors (such as obesity and mandibular retraction) to increase the risk of upper airway obstruction.
Studies have shown that approximately 30% of patients with severe septal deviation may also suffer from obstructive sleep apnea syndrome (OSAHS).
2. Symptom superposition
Nasal obstruction forces patients to wake frequently at night to adjust their breathing, which may mask or worsen the typical symptoms of apnea, such as snoring and waking up due to suffocation. Some patients may experience improvement in apnea symptoms after nasal septum correction.
3. Individual Differences
The degree and location of the deviation vary greatly, as do individual physical conditions. For example, a high-position deviation may significantly affect ventilation, and symptoms may be more aggravated in those with allergic rhinitis.
Symptoms and causes of nasal septum deviation
What are the symptoms of a deviated nasal septum?
A deviated nasal septum refers to the bending and deformation of the nasal septum in the middle of the nasal cavity due to developmental abnormalities or trauma. It may cause symptoms such as nasal congestion, headache, nosebleed, and decreased sense of smell. In severe cases, it may be accompanied by sinusitis or sleep disorders.
(1) Unilateral or bilateral nasal congestion
Most patients suffer from persistent nasal congestion, which may be unilateral or alternating between the two sides due to abnormal nasal structure, especially when suffering from a cold or rhinitis.
(2) Recurrent nosebleeds
The mucosa in the deviated area is thinner and the blood vessels are exposed, which makes it easy to rupture and bleed when stimulated by dry air or external force (such as picking the nose). The amount of bleeding is usually small but frequent.
(3) Headache or facial pain
The deviated part compresses the nerve endings on the side wall of the nasal cavity, which may cause dull pain in one side of the forehead, eye sockets, or face. The pain is often related to the degree of nasal congestion and worsens when lowering the head or feeling tired.
(4) Loss of smell
Long-term nasal congestion or inflammation may prevent airflow from reaching the olfactory area, which may cause a decrease in olfactory sensitivity, which can usually be partially recovered as the nasal congestion improves.
A deviated nasal septum can also be accompanied by other symptoms
Increased nasal secretions: Abnormal nasal structure affects the discharge of secretions, which may be accompanied by rhinitis or sinusitis, resulting in sticky and purulent nasal discharge and post-nasal drip.
Snoring or sleep apnea: Severe nasal congestion causes mouth breathing at night, which may cause snoring or even temporary hypoxia.
Stuffy ears or tinnitus: When the nasopharynx is inflamed or the Eustachian tube functions abnormally, a feeling of blockage in the ears or hearing loss may occur.
What causes a deviated nasal septum?
The main causes of a deviated nasal septum include congenital developmental abnormalities, trauma or external forces, nasal pathology, and degenerative changes. These factors, alone or in combination, can cause the cartilage or bone structure of the nasal septum to deviate from the midline, leading to symptoms such as nasal congestion and headaches.
(1) Congenital developmental abnormalities: During fetal development or adolescence, uneven growth rates between the nasal septum’s bones and cartilage can lead to structural deviations. For example, when cartilage grows faster than the surrounding bone, it can bend due to insufficient space. Additionally, some individuals may be born with abnormal nasal septum morphology, which gradually becomes apparent with age.
(2) Trauma or external force: Nasal trauma is a common cause, such as direct damage to the nose from sports collisions, falls, and car accidents, leading to cartilage or bone fractures and dislocations. Minor childhood injuries, such as bumps and bruises, can worsen the deflection with growth and development if not corrected promptly. Furthermore, long-term bad habits, such as nose picking and forceful nose blowing, can also affect the shape of the nasal septum through repeated irritation.
(3) Nasal lesions: Space-occupying lesions in the nasal cavity, such as polyps and tumors, or chronic inflammation, such as rhinitis and sinusitis, can exert persistent pressure on the nasal septum, causing it to gradually deviate from the midline. Furthermore, long-term unilateral nasal obstruction, such as adenoid hypertrophy, can lead to uneven airflow pressure during breathing, indirectly causing deviation.
(4) Degenerative changes: Elderly individuals may gradually develop a deviated nasal septum due to age-related changes such as decreased cartilage elasticity and bone resorption. This type of deviation typically progresses slowly and may contribute to symptoms along with nasal mucosal atrophy.
(5) Other influencing factors
- Gender and genetics: The incidence rate in men is slightly higher than that in women because of their more prominent facial bones and higher risk of trauma; some families may have a genetic tendency to abnormal nasal septum development.
- Iatrogenic factors: Nasal surgery (such as rhinoplasty, sinus surgery) may damage the stability of the nasal septum if it is not performed properly.
How does a deviated nasal septum affect breathing?
Nasal airflow is essential for good breathing, as anything that narrows the airways can cause breathing problems. People with nasal congestion often open their mouths during sleep, a reflex that can lead to sleep-disordered breathing, including snoring and sleep apnea.
In addition, nasal breathing has two unique characteristics that distinguish it from mouth breathing:
First, the nose acts as a heating element. You may have noticed that if you breathe through your mouth, your mouth and throat feel very dry. However, the air passing through the nose is slightly warmed and reaches the lungs at a more comfortable temperature for the body.
Secondly, the nose filters dust particles and other pollutants we inhale from the air. Furthermore, the nose contains specialized sensors that transmit information about airflow passing through it to the brain’s respiratory centers. Using these sensors, the nose actively participates in controlling and managing breathing. Without these sensors, we would not be able to accurately understand how much air is entering our lungs.
The nasal septum is a cartilaginous structure that separates the left and right nasal cavities. If it becomes significantly deviated, it may cause the following problems:
- Nasal stenosis: The deviated part compresses one side of the nasal cavity, reducing the ventilation space and causing airflow obstruction during breathing.
- Difficulty breathing: A deviated nasal septum may cause the nasal cavity to narrow, increasing the resistance when air enters and exits the nasal cavity, resulting in uncomfortable symptoms such as difficulty breathing.
- Mucosal irritation: The deviated part may repeatedly rub against the nasal concha, causing chronic inflammation or edema, further aggravating the obstruction.
- Olfactory impairment: A deviated nasal septum can affect the flow of secretions in the nasal cavity, causing mucus accumulation, which in turn affects the receptor function of the nasal mucosa and may even cause olfactory impairment.
- Nose bleeding: The airflow in the nasal cavity directly hits the deviated part, or is touched by the fingers, which makes it more susceptible to damage. A deviated nasal septum may cause nosebleeds.
- Nasal congestion and headache: A deviated nasal septum can cause nasal congestion on one side. As the condition progresses, the nasal mucosa on the other side may compensatorily thicken, leading to bilateral nasal congestion. Furthermore, the bony ridge can pierce the inferior or middle turbinate, causing reflex headaches.
- Cause inflammation: A deviated nasal septum may block the sinus drainage opening, causing rhinitis, sinusitis, or fungal rhinitis.
- Compensatory mouth breathing: Long-term nasal congestion may make people accustomed to breathing through their mouths, causing the root of the tongue to fall back during sleep, increasing the risk of upper airway collapse.
Intervention and treatment of nasal septum deviation
We need to evaluate the severity of nasal septal deviation. If accompanied by persistent nasal obstruction, recurrent epistaxis, headaches, or confirmed obstructive sleep apnea syndrome (OSAHS), we recommend seeking medical attention. Nasal endoscopy and CT examinations are performed to determine the degree of deviation, and polysomnography (PSG) is used to assess the severity of apnea.
Nasal septum deviation can be treated through conservative observation, septoplasty, septoplasty, medication, physical therapy, etc.
1. Conservative observation: Mild septal deviation without obvious symptoms can be left untreated, with regular nasal checkups. Avoid forceful nose blowing or picking to prevent mucosal damage. If you also have allergic rhinitis, reduce exposure to allergens such as pollen and dust mites.
2. Septoplasty: This surgery is indicated for conditions such as persistent nasal obstruction and sleep apnea caused by severe septal deviation. The procedure involves removing some of the deviated cartilage and bone to restore nasal ventilation. Postoperative hemostatic packing is required for 1-2 days. This condition may be related to congenital developmental abnormalities or post-traumatic healing malformations and is often accompanied by turbinate hypertrophy.
3. Septoplasty: A modified cartilage-preserving procedure can be used for adolescents to correct the deviation by reshaping the cartilage. This procedure reduces blood loss and the risk of perforation, making it suitable for patients with chronic sinusitis. Temporary hyposmia may occur after surgery, but typically resolves within 1-3 months.
4. Drug treatment: For secondary symptoms, budesonide nasal spray can be used short-term to reduce mucosal edema, and physiological seawater nasal spray can be used to keep the nasal cavity moist.
5. Physical therapy: Nasal irrigation can clear secretions and improve ventilation. Low-frequency pulsed electromagnetic field therapy can help relieve neuralgic headaches caused by deflection and compression. However, this method cannot change the deflection of the bony structure and is intended only as an adjunct.
Patients with right nasal septum deviation should maintain indoor humidity at 40%-60%, and wear masks when going out in winter to reduce cold air stimulation.
